Effect of intestinal resection on hydrogen sulfide biosynthesis and the damage of Cajal interstitial cells

Abstract

To investigate the effect of intestinal resection on hydrogen sulfide (H2S) biosynthesis and interstitial cells of Cajal(ICC) in mice. After intestinal resection mouse model was established, the activity of MPO in the proximal anastomosis intestinal tissue were detected. Sensitive sulphur electrode assay was applied to measure the H2S level. RT-PCR technique was employed to investigate the mRNA expression of the endogenous H2S biosynthesis enzymes, cystathionine-b-synthase (CBS) and cystathionine-c-lyase (CSE). Immunofluorescence staining was used to detect the expression of c-kit in order to calculate the area of ICC. The mRNA expression of CSE was detected in the small intestine tissue of mice, while no CBS mRNA was found. The mRNA expression of CSE in proximal anastomotic stoma increased in time-dependent manner in the model group. CSE mRNA expression began to increase 1 hour after operation, reached the peak at 6th hour, then decreased gradually, and was similar to the control group at postoperative 24th hour. Compared to the model group, in the intestinal tissues of proximal 3 cm to anastomotic stoma, the mRNA expression of CSE (1.16 ± 0.18 vs. 1.63 ± 0.13, P<0.05), the activity of MPO [(0.54 ± 0.07) U/g vs. (0.83 ± 0.09) U/g, P<0.05], the H2S level [(36.1 ± 6.1) nmol/mg vs. (5.3 ± 5.6) nmol/mg, P<0.05] were significantly reduced in the PPG group. Meanwhile, average percentage of positive ICC area in the PPG groups was significantly higher [(2.26 ± 0.19)% vs. (1.65 ± 0.24)%, P<0.05]. Inflammatory reaction in muscular layer induced by intestinal resection up-regulates the mRNA expression of CSE proximal to anastomotic stoma, generates excess H2S to damage ICC leading to intestinal motor dysfunction. Preoperative inhibition of endogenous H2S generation may protect the ICC.